After winning Commonwealth Games gold in October 2010, Johnson wasted no time in turning pro, signing with promoter Frank Warren and making his debut in December.

At Glasgow’s Braehead Arena, with Prince Naseem Hamed as his manager, the Bostonian beat Philip Townly by TKO in the second round, Townley’s first stoppage.

Johnson fought twice in 2011, two points victories against Jody Meikle, again at the Braehead Arena, and Lee Duncan at Liverpool’s Echo Arena.

A return to Glasgow - where he was a fan favourite after representing Scotland as an amateur - saw Johnson knockout Irishman Tommy Tolan in March 2012.

James Tucker was victory number five two months later, a seventh round TKO at Manchester’s Bowlers Exhibition Centre.

Johnson didn’t fight for another 12 months, but in May 2013 - his only fight of that year - he defeated James Anthony, who was disqualified for persistent holding, at Walsall Town Hall.

That was to be Johnson’s final fight with Warren as his promoter.

Four fights were staged in 2014, his most prolific year as a pro, with victories against Egidijus Kakstys (TKO) in Lincoln, Nathan King (points) at the Braehead Arena, Luke Allon (TKO) at the First Direct Arena, Leeds, and Josef Obeslo (TKO) in Lincoln.

Three fights followed in 2015, wins number 11, 12 and 13 coming at the expense of Bartlomiej Grafka (TKO) in Grantham, Jose Manuel Iglesias (KO) back in Keeds and Tzvetozar Liev (points) at the Echo Arena.

The following year saw Johnson beat Richard Horton at the Manchester Arena and Norbert Szekeres at Event City, Trafford Park, both by TKO, before concluding 2016’s action by claiming the vacant Commonwealth title, defeating Wilbeforce Shihepo by knockout in the ninth at the Manchester Arena.

Johnson didn’t fight in 2017 as he battled injury, but in March of this year he returned to stop Frank Buglioni in the first round at London’s 02 Arena to claim the British title.